Automatic Power Factor Correction (APFC)

Google "automatic power factor correction equipment"

power factor is that factor which is when low then make the usefull powe low and increase the waste power and when high then increase use full power .soppose we have 500 kva DG ,we can take 250 kw power from it if our power factor is 0.5 and if power facter is 1.0 then we can take 500 kw from 500 kav so we need to improve power factor for which we have to add attomatic factor correction panel is used.

Suppose dg 500 kva and power facter 0.5 Then

KVA=500

Kw= 500*0.5=250

Kvar=500-250=250kw ,APFC increse power factor by reducing angle between Voltage and Current or we can say by using capestive ckt in parrel of induction ckt we can minimize induction effect created by inductive ckt like moter ,inductive coil etc which are responsible for decreasing power factor

A simplified description of auto PFC control is a unit that stores energy from the line then reinserts that energy in a controlled manner so to correct the V-I relationship as seen by the supply side.

look at the merlin Guerin PFC controller site. If i remember correctly it has some nice animation and explanations

Chas

It takes years to learn all the details.

You can search this site for some discussions about capacitors and harmonics for a start.

While figuring out the required bank size is simple, the potential problems with resonances, harmonics and transients are not. If your application is simple, you will be OK but if you have a complex electrical plant supply, hire an expert. You will gain system reliability.

I have seen many systems sized and installed by the sales man. They initially work most of the time but some cause more problems than they solve. Most of them are not operational after ten years because the addition of AC drives in the plant has overloaded the capacitors banks or resonances have appeared and the customer leave them off to avoid equipment trips.

Good luck.